With the improving requirements on water environmental quality in China, the sewage treatment capacity is increasing year by year, so the amount of sludge as a byproduct is rising. The sludge is typically treated with conditioning and dewatering prior to further treatment such as incinerating, landfilling, composting, and recovering as building materials and the like. In the conventional wastewater treatment process, the obtained sludge typically has moisture content of up to 97%, and the sludge is a hydrophilic organic aggregate consisting mainly of extracellular polymeric substances (EPS) with villous branches and mesh structure, and the particles therein have irregular shapes and large porosity; and the sludge has high content of organic compounds, therefore it is easy to corrupt and stink; and it is difficult to dehydrate because of high moisture content.
At present, the amount of issued technical solutions for dissolving EPS is not very large. The first solution is the use of α-amylase to enhance the performance of sludge dehydration; the second one is adjusting the flocculent structure and the arrangement of the particles of the sludge by ultrasonic, changing the particle size of the sludge meanwhile recombining the particles of the sludge, and destroying the bacteria micelle structure of the sludge, so as to convert the bound water into free water and release it; the third one is adding an enzyme to make a deep dehydration to the biochemical sludge obtained in the paper industry; and the fourth technical solution is adding a composite conditioner containing potassium permanganate (fungicide), ferric chloride, lime, coal and other components, then the conditioned sludge is subjected to pressure squeezing under 6.5 MPa for 20 min, and the obtained mud cake has a moisture content below 40%. However, the present inventors have found that, in these existing solutions of physical, chemical conditioning above-mentioned only the interstitial water and capillary water can be removed, but the highly hydrated charged flocculent matrix and the EPS in the sludge cannot be destroyed, and the compression performance of the flocculent materials cannot be changed. In the existing dewatering process of sludge under filter press, the outflow passage of the sewage is blocked because of the compression of the organic matter, as a result the water contained in the floccule mesh of the sludge cannot release at maximum degree, that is, the sludge cannot be deeply dewatered.